signKey method Null safety

String signKey(
  1. String key
)

Signs a Sec-WebSocket-Key header sent by a WebSocket client as part of the initial handshake.

The return value should be sent back to the client in a Sec-WebSocket-Accept header.

Implementation

static String signKey(String key)
    // We use [codeUnits] here rather than UTF-8-decoding the string because
    // [key] is expected to be base64 encoded, and so will be pure ASCII.
    =>
    convert.base64
        .encode(sha1.convert((key + webSocketGUID).codeUnits).bytes);